This work exposes the systemic inability of conventional operando experiments to capture transient phenomena like dendrite initiation in batteries. To address this, Heuristic Operando experiments are proposed: a framework where an AI pilot leverages physics-based digital twins to actively steer the beamline to predict and deterministically capture rare events. This proactive approach redefines experimental efficiency via an entropy-based metric that prioritises scientific insight per photon, neutron, or muon, serving as a blueprint for trusted autonomous battery laboratories.